ELECTROCHIMICA ACTA
·
2014
·
IF 4.086
Hongjiao Nie,Yining Zhang,Wei Zhou,Jing Li,Baoshan Wu,Tao Liu,Huamin Zhang
The direct effect of nitrogen content and various nitrogen species on oxygen reduction reaction (ORR) activities in non-aqueous lithium-oxygen (Li-O 2 ) batteries are systematically investigated. Mesoporous carbon (MC) with various nitrogen species is prepared through heat treatment of N-containing precursor under different temperature. The effect of the heat treatment temperature on the performance of carbon materials in Li-O 2 battery is investigated. The bonding state of nitrogen atoms is found to have a significant effect on the ORR activity. The ORR activity in Li-O 2 battery is proved to be dependent on the quaternary N content while the total N content in the carbon material does not play a crucial role in the ORR process.
研究领域:
电化学
·
能源材料
·
纳米材料
·
电催化
·
锂离子电池
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·Vol. 45
·期 5
·117112
·
IF 5.8
Yaqian Du,Jianbo Li,Jun Wang
Compared with perovskite SrTiO 3 , SrO(SrTiO 3 ) 2 exhibits lower thermal conductivity , while maintaining a high Seebeck coefficient , making it a promising material for photothermoelectric conversion. However, the relationship between its infrared and thermoelectric properties remains unexplored. This study examines the effect of Gd doping on these properties of SrO(SrTiO 3 ) 2 . Increased Gd doping induces a gradual transformation of SrO(SrTiO 3 ) 2 -based into a SrTiO 3 -based material, resulting in a composite comprising three phases and a notable reduction in thermal conductivity . At 973 K, the thermal conductivity decreases to a minimum of 1.4 W m −1 K −1 , which is 23 % lower than undoped SrO(SrTiO 3 ) 2 and 51 % lower than SrTiO 3 . Like SrTiO 3 , SrO(SrTiO 3 ) 2 absorbs infrared radiation in the 8–14 μm range. Although the highest ZT value reaches only 0.06 at 973 K, it shows a positive correlation with infrared emissivity. These findings are valuable for advancing the application of thermoelectric effects and the development of high-performance infrared materials.
研究领域:
材料科学
·
凝聚态物理
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功能材料
·
能源材料
·
红外光学
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2021
·Vol. 65
·期 5
·1285-1293
·
IF 8.273
Zheng Mang,Li Qi,Liu Mingyang,Liu Jianan,Zhao Chen,Xiao Xudong,Wang Hongli,Zhou Jing,Zhang Liping,Jiang Baojiang
As an n-type semiconductor, In 2 O 3 is considered a promising photocatalyst for producing amino acids using biomass derivatives as precursors. However, similar to other intrinsic semiconductors, In 2 O 3 suffers from poor charge dynamics. Herein, we show the synthesis of Mo-doped In 2 O 3 (Mo-In 2 O 3 ) with a porous rod-shaped structure through a one-step solvothermal reaction followed by calcination. Under visible-light irradiation, Mo-In 2 O 3 achieves a high conversion rate of 81% for the reaction that transforms lactic acid into alanine with a selectivity of 91%. Spectroscopic techniques and density functional theory calculations reveal that Mo doping introduces defect states slightly below the conduction band of In 2 O 3 , which improves the separation of photogenerated electron-hole pairs. In addition, Mo atoms on the surface form extra adsorption and reaction centers that greatly enhance the reaction rate. This work provides insights into the development of transition metal-doped semiconductor photocatalysts to produce amino acids.
研究领域:
材料科学
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光催化
·
半导体材料
·
生物基化学品
·
分子催化
·
纳米材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Sujuan Wang,Qing Luo,Xiaohua Luo,Shengcan Ma,Changcai Chen,Fei Gao,Bodong Lv,Rui Zhong,Weijun Ren,Zhenchen Zhong
The effects of Si and Cu doping on crystal structures, magnetism , and the magnetocaloric effect of EuAl 4 have been investigated. EuAl 4 , EuAl 3.35 Si 0.65 , and EuAl 3.82 Cu 0.18 single crystals grown by the Al flux method are isotypic and crystallize in BaAl 4 -type structure with space group I 4 /mmm . Compared to the pristine compound EuAl 4 , the lattice parameter a keeps almost unchanged and c decreases obviously by Si doping, while a decreases and c increases upon Cu-substitution. These irregular changes in the lattice parameters may contribute to the electronegativity difference between Si and Cu. Cu and Si doping enhances the ferromagnetic interaction, and the direction of easy magnetization changes from the ab plane to the c axis upon the Cu-substitution. Multiple-step metamagnetic transitions are still observed in EuAl 3.35 Si 0.65 as applying the magnetic field along the c axis, while EuAl 3.82 Cu 0.18 shows ferromagnetic behavior along the ab plane and c axis. As a consequence, the low-field magnetocaloric effect is significantly enhanced. The maximum magnetic entropy change under a field change of 20 kOe increases from − 8.4 J/kg K for EuAl 4 to − 12.9 J/kg K for EuAl 3.35 Si 0.65 and − 15.9 J/kg K for EuAl 3.82 Cu 0.18 . The corresponding values of refrigerating capacity are 67, 140, and 147 J/kg, respectively. The remarkable magnetocaloric performances suggest that the Cu-doped EuAl 4 compound is an excellent candidate material for low-temperature magnetic refrigeration.
研究领域:
凝聚态物理
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材料科学
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磁学
·
低温物理
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 54
·期 8
·6451-6460
·
IF 3.442
Zhang Yixin,Liu Lei,Zhang Lili,Yu Yifeng,Lv Haijun,Chen Aibing
Carbon nanotube (CNT) has been intensively studied as supercapacitor electrode materials due to their high mechanical strength and excellent electrical conductivity. However, CNT with limited accessible surface area has low specific capacitance, which limits its application and development in supercapacitor. Herein, we have designed a thin N-doped porous carbon layer-modified CNT nanocomposite by template-free method. In this process, 3-aminophenol and formaldehyde rapidly self-assemble on the CNT in the presence of cationic surfactant CTAB, forming the composite of 3-aminophenol/formaldehyde (3-AF) resin and CNT. Due to the different polymerization degree of inside 3-AF resin, the soluble 3-AF resin oligomer was removed by acetone to form porous 3-AF resin and CNT@N-doped porous carbon (CNT@N-PC) was obtained by annealing process. The CNT@N-PC exhibited abundant porous structure, high specific surface area of 940 m 2 g −1 , excellent specific capacitance value of 224 F g −1 at 1 A g −1 and good cycle stability, demonstrating its potential as supercapacitor electrode materials.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Results in Physics
·
2022
·
IF 4.565
Yige Du,Qilong Gao,Andrea Sanson,Hengli Xie,Yangming Hu,Gaojie Zeng,Juan Guo,Xiao Ren,Erjun Liang
Negative thermal expansion (NTE) is an intriguing physical phenomenon, which is of great significance for the high precision application. In this work, we have realized to broaden the NTE temperature zone in Mg 2 P 2 O 7 -based bulk material by doping Cu atom on the Mg site. A joint study of Raman scattering and X-ray diffraction (XRD) indicates that there are double phases in the NTE temperature zone, and the NTE of Mg 1.9 Cu 0.1 P 2 O 7 bulk material comes from the phase transition of α - and β -phase. The present work provides a way to optimize negative thermal expansion property in phase transition typed materials.
研究领域:
材料科学
·
凝聚态物理
·
无机化学
·
功能材料
·
热学性能
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·Vol. 47
·期 5
·6842-6847
·
IF 3.83
Shunjin Xiong,Rongxia Huang,Congfei Peng,Yejing Dai,Jiajiu Li,Wen Bai,Hua-Tay Lin
A series of HfO 2 -modified (Bi 0 .475 Na 0 . 405 K 0 . 055 Li 0.015 ) 0.95 Ba 0 . 05 Ti (1- x ) Hf x O 3 ( x = 0–0.015) lead-free ceramics were prepared. Results of detailed characterizations showed that the addition of HfO 2 had little influence on the grain size, and all of the samples showed the pure perovskite structure. As the Hf 4+ content increases, the samples changed from the normal ferroelectric phase to the ergodic relaxor state at room temperature, and the ceramics with x = 0.01 showed a high electro-strain of 0.295% at 6 kV/mm. Therefore, this study provides a new insight into of how the HfO 2 addition influences the ferroelectric property of the BNT-based ceramics by B-site substitution.
研究领域:
材料科学
·
无机非金属材料
·
功能陶瓷
·
铁电材料
·
压电材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Shufang Chang,Yiwen Hu,Jun Qian,Yinlin Shao,Shuang Ni,Lulu Kong,Wenyan Dan,Chun Luo,Shu Jin,Xiaoxiang Xu
Nitrogen doped Mg 2 TiO 4 spinel, i.e. Mg 2 TiO 4−x N y , has been synthesized and investigated as a photocatalyst for antibacterial activity. Mg 2 TiO 4−x N y demonstrates superior photocatalytic activity for E. coli disinfection under visible light illumination (λ ≥ 400 nm). Complete disinfection of E. coli at a bacterial cell density of 1.0 × 10 7 CFU mL −1 can be achieved within merely 60 min. Mg 2 TiO 4−x N y is capable of generating superoxide radicals ( O 2 − ) under visible light illumination which are the reactive oxygen species (ROSs) for bacteria disinfection. DFT calculations have verified the importance of nitrogen dopants in improving the visible light sensitivity of Mg 2 TiO 4−x N y . The facile synthesis, low cost, good biocompatibility and high disinfection activity of Mg 2 TiO 4−x N y warrant promising applications in the field of water purification and antibacterial products.
研究领域:
材料科学
·
环境科学
·
微生物学
·
光催化
·
纳米医学
·
生物材料
✓ 已验证
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2016
·
IF 2.101
Yuyang Li,Guanghua Liu,Jiangtao Li,Kexin Chen,Gang He,Zengchao Yang,Yemao Han,Min Zhou,Laifeng Li
Bulk In-doped Cu 2 SnSe 3 samples were prepared by a fast and one-step method of high-gravity combustion synthesis . All the synthesized samples were dense with relative densities of >98%. The influence of Indium-doping on the phase composition of the samples was investigated. SEM and EDS measurements confirm the existence of SnSe and Cu 2 Se as secondary phase in the Cu 2 Sn 1−x In x Se 3 samples. In addition, the experimental results show that there is a solubility limit of indium in the Cu 2 SnSe 3 matrix. The thermoelectric properties of the samples were measured in a temperature range from 323 K to 773 K, and the Cu 2 Sn 0.8 In 0.2 Se 3 sample achieved a maximum ZT of 0.65 at 773 K, which was comparable with the best-reported result for Cu 2 SnSe 3 materials prepared by conventional sintering approaches. With much reduced time and energy consumption, high-gravity combustion synthesis may offer a more efficient and economical way for producing thermoelectric materials .
研究领域:
材料科学
·
无机非金属材料
·
热电转换
·
固态化学
·
功能材料
✓ 已验证
DOI
高影响因子
Results in Physics
·
2021
·
IF 4.476
Lin Bo,Yongpeng Wang,Wenying Wang,Lei Wang,Fujin Li,Min Zuo,Yanzhen Ma,Degang Zhao
The ternary Cu 3 SbSe 4 thermoelectric material with diamond-like structure exhibit good thermoelectric performance in the middle temperature region. In this study, the Cu 3− x Ni x SbSe 4 ( x = 0–0.03) materials were fabricated by melting-ball milling-hot pressing process. The influences of grain size and compositional gradient on the microstructure and thermoelectric properties of Cu 3− x Ni x SbSe 4 were evaluated. It is found that the electrical conductivity of Cu 2.97 Ni 0.03 SbSe 4 was about 33% higher than that of Cu 3 SbSe 4 sample, and the lattice thermal conductivity was reduced from 3.3 Wm −1 K −1 to 2.4 Wm −1 K −1 at room temperature due to the grain refinement and more V Se defects. The maximum zT value for the Cu 2.97 Ni 0.03 SbSe 4 sample was 0.62 at 650 K.
研究领域:
材料科学
·
凝聚态物理
·
功能材料
·
热电材料
·
半导体材料
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2017
·
IF 2.238
Jianjian Sun,Bijun Fang,Shuai Zhang,Zhihui Chen,Jianning Ding,Xiangyong Zhao,Haosu Luo
Er 3+ -doped Na 0.5 Bi 0.5 TiO 3 (Er-doped NBT) ceramics were prepared via a hydrothermal method . High sintering active Er-doped NBT nano cubic particles with perovskite structure were synthesized at hydrothermal condition of 200 °C for 24 h in 12 M NaOH solution, which were self-assembled via in situ crystallization mechanism by the initially as-grown nanowires. The Er-doped NBT ceramics sintered at 1100 °C for 2 h exhibit pure rhombohedral perovskite structure, high densification and rather homogenous microstructure morphology. Under 488 nm light excitation , the strong green emission peaks centering at 530 nm and 550 nm and the weak red emission peaks locating at 665 nm and 735 nm are excited, which can be attributed to the 2 H 11/2 , 4 S 3/2 , 4 F 9/2 and 4 I 9/2 → 4 I 15/2 transitions, respectively. The maximum emission intensity is obtained when the Er doping content reaches 1.0 mol%. A strong upconversion emission peak centering around 550 nm in green light range is excited under 800 nm light excitation, which is correlated with the 4 S 3/2 → 4 I 15/2 transition.
研究领域:
材料科学
·
无机非金属材料
·
功能陶瓷
·
光电子学
·
固体化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2016
·
IF 2.822
Yanmeng Cai,Yue Wang,Xinyu Han,Liwen Zhang,Shichang Xu,Jixiao Wang
The composites of carbon nanotube (CNT) and the conducting polymer polypyrrole (PPy) doped with dodecyl benzene sulfonate (DBS − ) and Cl − were prepared respectively by chemical oxidation method and made into two types of composite electrode (PPy-DBS/CNT and PPy-Cl/CNT) for capacitive deionization (CDI) cell. Enhanced electrochemical performance of the composite electrodes was confirmed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) test. The results of CV showed that the specific capacitance of PPy/CNT doped with either DBS − or Cl − was about 2.3–2.5 times that of the CNT electrode. And EIS test demonstrated that the charging resistance for both the PPy-DBS/CNT and PPy-Cl/CNT electrodes was dramatically reduced and only about 10% that of the CNT electrode. By pairing the two composite electrodes with CNT electrodes, four cells were assembled to study the effects of electrode assembling patterns on the desalination performance of the CDI process. The results indicated that the CDI cells involving either the PPy-DBS/CNT electrode or the PPy-Cl/CNT electrode, or both of them exhibited much higher electrosorption capacity (from 40.8 to 72.36 mg/g) than that of the CDI cell assembled with two CNT electrodes (about 12.6 mg/g). And the composite electrodes kept good stability and fast regeneration rate after several desalting cycles. Thus, it is believed that the enhanced performance and optimized electrode assembly of the CDI cell should be with the composite electrodes that have the good ability of ion selective adsorption for cations or anions.
研究领域:
材料科学
·
环境工程
·
电化学
·
水处理技术
·
功能高分子材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）